README file for 'Replication Data for "The energy budgets of giant impacts"'
Philip J. Carter, Simon J. Lock and Sarah T. Stewart, 2019,
https://doi.org/10.7910/DVN/YYNJSX, Harvard Dataverse.


This dataset contains data used to produce the figures found in the article:
"The energy budgets of giant impacts"
P. J. Carter, S. J. Lock and S. T. Stewart, 2019, JGR:Planets.

It also contains a table summarizing the simulations discussed in the article, 
as well as initial condition files for all of the simulations, and code for 
reading this file format.

The modified version of Gadget2 used to run these simulations is available from
the online supplement to Cuk, M. & Stewart, S. T. (2012), Science, 338, 1047:
www.sciencemag.org/cgi/content/full/science.1225542/DC1

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Contents of this dataset:

ForsteriteTable.txt - Finely gridded version of the Gadget forsterite EOS table
ForsteriteTable_orig.txt - Original gadget forsterite EOS table
IronTable.txt - Gadget iron EOS table
GItable.csv - Summary of the simulation parameters and energies
impact.param - Gadget2 parameter file for running impact simulations
gadget_snapshot.py - Python code for reading Gadget2 snapshot files
README - This readme file

inputfiles/ - Contains initial conditions for each simulation
                Snapshot files are detailed below
snapfiles/ - Output snapshots for the four example impacts in the article
                Used to produce Figures 1 and 8
timeseries/ - Time series data extracted for the four examples

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Snapshot files:

The snapshot files (both initial conditions and outputs) use an extension of 
the standard Gadget2 format with specific entropy stored in the 'u' block. The 
'_long' format includes additional blocks using the same structure for 
pressure P (GPa), temperature T (K), specific internal energy U (erg/g), and 
sound speed cs (cm/s).
                
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gadget_snapshot.py:

Python code for reading (long format) gadget snapshot files.
Implements the Snapshot class for a gadget snapshot. Contains a brief 
example of how to use the code.
                
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GITable.csv:

Lists simulation label, target mass (Earth masses), target radius (km), number 
of SPH particles in target, spin angular momentum of target (in units of 
Earth-Moon angular momentum), angular velocity of target (rad/s), projectile 
mass (Earth masses), projectile radius (km), number of SPH particles in 
projectile, spin angular momentum of projectile (in units of Earth-Moon angular 
momentum), angular velocity of projectile (rad/s), impact velocity (km/s), 
impact parameter, modified specific energy of the impact (J/kg), initial 
potential energy (J), minimum potential energy (J), potential energy at 24 
hours (J), initial kinetic energy (J), kinetic energy at 24 hours (J), initial 
internal energy (J), internal energy at 24 hours (J), and the EOSflag.

The EOS flag indicates whether the simulation used the original forsterite 
table (o) from Cuk & Stewart (2012), or the more finely gridded version (f) 
supplied in this dataset (ForsteriteTable.txt).

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timeseries/
*_MantleEntropyStructure.txt/*_CoreEntropyStructure.txt:

These files contain the data used to produce Figures 10 and 11.
The format is as follows:

Number time elements,
times,
Number mass elements,
masses,
Number pressure elements,
pressures,
Number x elements, Number y elements,
x matrix rows containing specific entropy (kJ/K/kg)

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timeseries/
*_EBudgetTimeSeries.csv:

These files contain energy time series for the example simulations.

Table of times (hours), total energy (J), total energy budget using 
participating potential energy (J), potential energy (J), participating 
potential energy (J), kinetic energy (J), internal energy (J), participating 
potential energy of bound material (J), participating potential energy of 
ejecta (J), kinetic energy of bound material (J), kinetic energy of ejecta (J), 
internal energy of bound material (J), Internal energy of ejecta (J).

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impact.param:

Parameter file for Gadget2 for running impact simulations.
Set InitCondFile to the required input file.

Simulations M99p2.3M05v20br0.3avh2 and M99p2.3M05v20br0.3avl2 use the same 
initial condition, and differ from the other simulations by having 
ArtBulkViscConst set to 1.6 and 0.4 respectively.


